Run worker over items with at most limit concurrent executions. Results are
returned in input order. The worker is responsible for its own error handling — a
rejection from one item propagates, so dispatcher callers wrap each routine's work in
its own try/catch (per-routine error isolation).
Run
workeroveritemswith at mostlimitconcurrent executions. Results are returned in input order. The worker is responsible for its own error handling — a rejection from one item propagates, so dispatcher callers wrap each routine's work in its own try/catch (per-routine error isolation).